1. Field of the Invention
The invention relates to a film deposition device and a film deposition method of a metal film, in particular, a film deposition device and a film deposition method of a metal film, which can deposit a thin metal film uniformly on a surface of a base material.
2. Description of Related Art
Heretofore, when an electronic circuit base material or the like is manufactured, in order to form a metal circuit pattern, a metal film is deposited on a surface of a base material. For example, as a film deposition method of such a metal film, a film deposition technique in which a metal film is deposited on a surface of a semiconductor base material such as Si by plating such as electroless plating or the like (see Japanese Patent Application Publication No. 2010-037622 (JP 2010-037622 A), for example) and a film deposition technique in which a metal film is deposited by a PVD method such as sputtering have been proposed.
However, in the case where plating such as the electroless plating was applied, water cleansing was necessary after the plating, and an waste liquid after water cleansing was necessary to be treated. Further, when a film was deposited on a surface of a base material by a PVD method such as sputtering, since an internal stress was formed in a deposited metal film, a film thickness was limited from being thickened, in particular, in the case of sputtering, in some cases, the film deposition was possible only under high vacuum.
In view of points like this, for example, a film deposition method of a metal film, which uses a positive electrode, a negative electrode, a solid electrolyte membrane disposed between the positive electrode and negative electrode, and a power supply part that applies a voltage between the positive electrode and negative electrode is proposed (see JP 2012-219362 A, for example).
Here, the solid electrolyte membrane is formed in such a manner that a solution containing a precursor of a solid electrolyte is spin coated on a surface of a base material in advance and cured, and metal ions to be coated on the solid electrolyte membrane are impregnated. Then, the solid electrolyte membrane is faced to the positive electrode and the base material is disposed so as to be electrically connected with the negative electrode. By applying a voltage between the positive electrode and negative electrode, the metal ions impregnated inside the solid electrolyte are precipitated on a negative electrode side thereby. Thus, a metal film made of metal of the metal ions can be deposited.
However, when the technique described in Japanese Patent Application Publication No. 2012-219362 (JP 2012-219362 A) was used, in some cases, in a contact part (contact surface) between the solid electrolyte membrane and the base material, irregularities in contact pressure were generated. When a metal film is deposited in a state in which such irregularities of contact pressure were generated in a region where the metal film is deposited of a surface of the base material, there was a possibility of inducing irregularities in a film thickness of the metal film.